Depends on what your server is used for...
If stability is your number 1 concern, I would say stay away from dual via chipsets, there are still pretty new and people are having compatibility problems left and right. Most problems are solved, but if you are not into hardware and like to challenge yourself on a regular basis, stay away from via. But if you use the server for your home, and you are good in stuff like tweaking the memory, troubleshooting incompatibility problems, via is still a good option.
If you want stability and don't want to mess with the hardware after you get everything assembled, get a BX mobo like Tyan Tiger 100 rev F, cheap and performs great. If you want the top of the line, and don't use AGP, use Serverwork LE chipset mobos (Supermicro 370DL or something). If you want the ultimate mobo, use Serverwork HL chipset, with AGP Pro, 64bit pci...etc. Expansive and hard to find though. (Tyan thuander2500) Only problem, you need to use registered memory for serverwork chipsets like most server grade mobo.
Or you can wait til AMD760MP dual chipset comes out (early-mid 1st Q 2001), together with Palomino release and DDR support......that's gonna be one killer system!!